I typed "cheese pizza" into the database and got a plethora of results including all of the major pizza chains. Click on the link and you get the nutritional information as well as some useful nutritional ratings from the experts from the site.

Good database of nutrition information for a variety of foods. Doesn't seem to contain information for a lot of brand-name packaged foods, though. This is better for looking up more basic ingredients.

This is a really cool page that allows you to select a food and find out its nutritional facts, caloric ratio, and nutrient balance. Great resource!